Question for the experts on fiberglass dust

[Woodonglass]

Re: Question for the experts on fiberglassing a 1976 ProCraft 1500 tri-hull

Re: Question for the experts on fiberglassing a 1976 ProCraft 1500 tri-hull

When using Polyester resin you cannot just use cloth. Without getting into Chemistry to much the basic fact is Poly requires CSM to "Bind" the resin molecules together and keep it from cracking. If you go to OOPS thread you can read much more about this. Suffice it to say that when using Poly CSM is required... when using Epoxy, CSM is not used. 1708 is a 17 oz cloth with CSM stitched to it. The pro's all say that it is best to still use a layer of 1.5 oz CSM in conjunction with the 1708. The CSM stitched to the 1700 cloth is a thin layer and needs more CSM to ensure a good bond. Hope that clarifies things a bit.

 

[ondarvr]

Re: Question for the experts on fiberglassing a 1976 ProCraft 1500 tri-hull

Re: Question for the experts on fiberglassing a 1976 ProCraft 1500 tri-hull

When using epoxy you can eliminate the CSM. The difference between the two (polyester and epoxy) is that polyester tends to be weak and brittle compared to epoxy.
When a fabric (not CSM) is used alone the loft of the material allows extra resin to pool in the fabric, plus between it and the substrate or between layers, this resin rich (or resin only) layer can be rather weak compared to the areas with the correct amount of glass. It is this weak resin rich layer that will fail when the laminate is stressed. When CSM is used the random fibers in it tend to fill those areas in the laminate that would have only contained resin without it, so there is less unreinforced resin, resulting in more strength.

Sometimes it is said the bond is better with CSM (I say it too), actually as far as the resin is concerned the bond is the same either way, it’s just that there is no resin rich layer to fail when CSM is used.
People will frequently use a layer of CSM under 1708 (or similar products), because while the amount of CSM attached to it works well between the layers in a laminate done all at one time, it may not be quit enough for the first layer against the substrate.

 

[blkvyyper]

Re: Question for the experts on fiberglassing a 1976 ProCraft 1500 tri-hull

Re: Question for the experts on fiberglassing a 1976 ProCraft 1500 tri-hull

WOG and Ondarvr,
Thanks for clearing that up...I will use the 1708 and CSM as you say...I read Oops! thread, the man is unreal...wish i had him doing this..LOL. Would love to use epoxy but geez the stuff is expensive. Trying to cut cost in one spot and just gets refilled in another.

Anyone wanna send any donations!!! I take checks, cash, credit card numbers, paypal, yourpal, hispal, anybodypal...LOL. Gotta laugh to keep from crying. Spent most of the past year building a building to house the renamed procraft to the "ole shucky duck". Even gor a wood stove in it. all the wood was given accept for an addition i did on it. It's 26x12 with a 15x15 additon on it. The ole lady wired the electrical to it from the house breaker box. yeah got one of them types. Rather do electrical and plumbing and fish than do girl stuff.

 

[Woodonglass]

Re: Question for the experts on fiberglassing a 1976 ProCraft 1500 tri-hull

Re: Question for the experts on fiberglassing a 1976 ProCraft 1500 tri-hull

Now THAT's a SWMBO to be Admired.!!!!!

 

[blkvyyper]

Re: Question for the experts on fiberglassing a 1976 ProCraft 1500 tri-hull

Re: Question for the experts on fiberglassing a 1976 ProCraft 1500 tri-hull

Your right about that WoG, she's gone now to re-wire a refrigerator and weld a towing trailor...she also does PLC's ( programmable logic controllers). This programs computers to talk to other computers to do things...like in a industrial setting. Can't get her to sand my boat though...LOL. Maybe i can get back on my boat now...LOL. Anybody know why the "honey do" list seems to be always on wednesday....LOL

 

[Woodonglass]

Re: Question for the experts on fiberglassing a 1976 ProCraft 1500 tri-hull

Re: Question for the experts on fiberglassing a 1976 ProCraft 1500 tri-hull

Anybody know why the "honey do" list seems to be always on wednesday....LOL

That's so you have to "Hump" to get through it.

 

[blkvyyper]

Re: Question for the experts on fiberglassing a 1976 ProCraft 1500 tri-hull

Re: Question for the experts on fiberglassing a 1976 ProCraft 1500 tri-hull

LOL good one...well while she was gone, got the ole "shucky duck" off the trailer to assess the bottom of the hull more carefully. mostly scraps and junk...few spider eggs...lol. anyway what can you use besides the carpet on the bunks on the trailer? I attached some pics so you guys can give me some insight on what you would do. Also how do get the correct height for the bunks in relation to the rollers so the boat doesn't get all scratched up again.

Should i grind out all the old patch work and redo it with PB, CSM and 1708 or just grind them down and leave them? I've already been told how to tackle the stem and strake breaches. Anyone tried that UV resin? any good or bad thoughts about it?

Thanks,
BV

 

[blkvyyper]

Question for the experts: What would you do?

Question for the experts: What would you do?

Hello Gents,
Hope all is well. Well it's fair time here in NC so No honey..No honey-do list...so what does that mean...yep more sanding on the "shucky duck". I know you guys will probably cringe when you see what i done, but that's what us noobs do...especially when your a somewhat perfectionist...LOL I got the "duck" of the roost (trailer) and was initially gonna grind out the bad spots, but got carried away and sanded the gelcoat off most the bottom of the hull. Besides you can really see where the repairs need to go when they aren't being hidden gelcoat, thin spots and all. So I ask the experts, besides doing these minor repairs, would you:

a) give the bottom a transom another full coat of fiberglass before gelcoat

b) re gelcoat it and call it a day

Do i need to primer it before i gelcoat? PPG makes a thick primer good for filling in pinholes and all, which i was thinking of doing, then wet sand, then gelcoat.

Also another question i have, I know the famous Oops! and others have mentioned putting glass in between the sandwiched wood of the new transom. As you can see from the pics i included, i ground the back of the skin and the inside of the skin is ground also. Would it be feasible or not to use the skin in between the two halves of the wood for the transom? Any Pros or Cons to that? Just an idea I thought about when i finished grinding it.

Man you think fiberglass grinding produces dust, try grinding gelcoat! it was snowing 70 degree weather...LOL! I was using 24 and 36 grit sanding discs on harbor freight 4 1/2" and 7" grinders so it went quick. I also have not burned up anyone of them and i've grinded the inside and outside of the boat. But I also keep them blown out with compressed air and grind outside, so that may help. Trying to get all the grinding done before it gets cold so i can move my "ole duck" into the shop with the wood stove this winter for glassing hopefully. Any sanding then can be done with the handheld with a vac attachment.

Thanks...

BV

 

[ondarvr]

Re: Question for the experts: What would you do?

Re: Question for the experts: What would you do?

It gets more difficult when you grind off the gel coat, you will expose millions of tiny air pockets in the laminate and these will haunt you when trying to re-coat it.

There is no need for primer, but you do need to fill all those tiny holes with something, and the easiest way is to squeegee gel coat over the surface before you spray it with gel coat. Otherwise you won't be able to easily cover them and they will still be there later when the gel coat is hard.

 

[blkvyyper]

Re: Question for the experts: What would you do?

Re: Question for the experts: What would you do?

Thanks Ondarvr for the reply,
now that you said that, i do remember seeing some tiny air pockets especially around the edges in some places. Thats why I thought about doing a prime layer first to seal it so to speak. I had planned on sanding the whole hull but after you said that, better stop while i'm a few feet ahead...

Thanks...
BV

 

[Georgesalmon]

Re: Question for the experts: What would you do?

Re: Question for the experts: What would you do?

Thought I'd put .02 in here. Gelcoat really doesn't need a primer to stick like many paints do. Gelcoat is just polyester resin with a bunch of stuff mixed in like;pigments, thixotropic agents such as fumed silaca or ground walnut shells (really) and UV protectection, plus other things so the manufacturer can claim that their gelcoat is the "best". The part about tiny microscopic holes is true. Spraying gelcoat can be tough when little holes in the substrate cause what looks like fish eyes. That's usually not a problem when brushing or rolling. There are some polyester primers out there made to use under gelcoat but most need to be sanded nice and smooth before gelling over them. Twice as much work. You can use a toothpick to close a few holes while your spraying and still wet. If you got lots of holes stand by with a brush. One way might be to spray a coat of gelcoat and brush the holes, then sand it and spray another coat. Whatever you do its a lot of work to get a nice gelcoat finish which is why many paint their boats instead. Some very high grade manufacturers just use a special type of gelcoat in the mold and sand and paint after the boat is finished.

 

[blkvyyper]

Re: Question for the experts: What would you do?

Re: Question for the experts: What would you do?

Georgesalmon,
Thanks for the reply, I appreciate the response. Man do I feel stupid...thought i was starting with a clean canvas so to speak. Seems I just put more work on myself. I plan on brushing and tipping even though i do have a sprayer. Well how about this idea,how about rolling and brushing instead of spraying it first...then coming back with a layer of spray? This will be my first time using gelcoat so i really have no idea how it works or handles. Like i said in my previous post...PPG makes a think primer for autos that fills in imperfections like pinholes and low spots. I think what i'll do is try a small section and see how it works. If not, guess I'm pushed back even further with my build. Either way, I appreciate all you guys and your help. Should have consulted with you guys before i did so much sanding and grinding. I posted a question that hadn't been answered yet about the transom build. I thought about using the transom skin as the insert between the two pieces of would to build the transom. Just a thought, don't wanna make another big mistake I'll regret...LOL

BV

 

[Woodonglass]

Re: Question for the experts: What would you do?

Re: Question for the experts: What would you do?

BV, you really should spend some time researching, reading and studying on how to apply gelcoat. OOPS thread is a good starting point. He explains it all very well. It is NOTHING like applying paint.

 

[blkvyyper]

Re: Question for the experts: What would you do?

Re: Question for the experts: What would you do?

WOG,
I have been researching and most of what i find has nothing to do with a ground bare hull, all i find is about sanding the gelcoat and reapplying it. None on if i should build up the ground material first, or just add filler. So yeah i'm still doing my research and re reading Oops! thread.

Thanks for the reply,
BV

 

[Georgesalmon]

Re: Question for the experts: What would you do?

Re: Question for the experts: What would you do?

If you brush and/or roll the gelcoat on first and sand it smooth, then a spray will be easier to finish out. Expect to do a lot of wet sanding and buffing to get a nice shiny finish like you would get with paint.

 

[Woodonglass]

Re: Question for the experts: What would you do?

Re: Question for the experts: What would you do?

Yacht Dr. Posted this on Deckers thread yesterday.

Not sure what you mean by building up the ground material? The hull should be as Flat and as smooth and straight as you can get it. Just like paint the gelcoat will show any imperfections. You can make your own fairing material from resin, glass bubble and a bit of cabosil. Once it's the way you want it, you shoot the gel as described below.

Yesterday, 07:16 PM
#468
Yacht Dr.

Rear Admiral

Join DateFeb 2005
Location Michigan
Posts 4,444

Re: 1983 Deck Boat Transom/deck/stringer replacement Help

Sorry I missed this thread for so long .. it was going every where and I lost track..

I think I will ask the Mods to post a sticky up there about Gel applications ..

When your ready to Spray Gel Coat .. You Spray ALL coats at the same time.

You GO GO GO .. until All applications are applied.

You dont stop between .. you dont sand between .. you dont wax between .. you just Apply.

Yes there are additives that you can mix in the gel for "patches".

Best thing for a full blown gel job is to reduce your gel as thin as possible ( Buy a qt of cheep crap latex paint and see how your gun works .. then flush it with water .. then flush it with acetone ).

It all depends on how well you spray your gel on .. could be 3-5 times. If its heavy on the orange peel.. you might want to put one more (sand) coat on. (thin the last coat and spray it like paint to remove the Peel).

Lastly you want to apply the PVA .. the green stuff. Do NOT Inhale and treat this like Toxic.

I use the test of just tacky enough to touch it and leave a print without Inprinting the gel.

Then GO Go with the PVA ( Which sprays water thin and Fast ).

Flush your gun after your gel with acetone .. then flush it with water .. then spray PVA .. then flush it with water .. then final flush with acetone. ( you cant mix acetone with PVA ) is the reason for so many flushes with the same gun.

Any more questions PM me just to make sure . I will post them in your thread.

YD.
​

All Information or advice given by ME is from a Professional point of view and does not discount other methods by other members of Iboats.

​

 

[blkvyyper]

Re: Question for the experts: What would you do?

Re: Question for the experts: What would you do?

WoG, GeorgeSalmon
Thanks for the reply, I'll make sure to follow what it says, and thanks for the tips. It's very much appreciated. Guess I made a noob mistake...eh that's why we noobs right...LOL "gotta laugh to keep from cryin!!!"

Also gotta 2 questions for whomever can answer this...i asked one before but got no answer on it. On some of the older boats and it might be on some of the newer boats, i don't know. There is a "drain plug" I call it on the front starboard side which i have no clue what it was used for. Does anyone know?

The second question is if you look at my previously posted pics where i sanded the outside skin of the transom. There are drainage plugs at the bottom of it. But there is also this brass looking ring that i left on "for now". Any clue what it is? It was gelcoated over and has a very small hole through it. To small for a plug to go in it.

Thanks,

BV

 

[jbcurt00]

Re: Question for the experts: What would you do?

Re: Question for the experts: What would you do?

Re: Q #1:
The white drain, directly above the BM at the end of your Reg#, shown in this pix:

It's a drain for something in the bow of the boat... The bow storage compartments, to empty a live well or other.

Here's another pix you posted of it:

Re: Q #2
The brass drain shown in the center of this pix:

Directly over the 'R' in the word 'more'?

Does it have screw threads on the inside?
If so, garboard drain...

Do you have a resto thread started for this boat?

BV is back with another noob question about fiberglass dust. We all know you generate a ton of the stuff when sanding and grinding. My question is can it be re-used as a resin thickener? Since people use wood flour and chopstrand and cabosil to thicken resin for PB, was wondering if it could be used as a thickener. Also I'm working on a 76 procraft tri-hull

Might post these questions there, instead of in a 'Can I recycle fiberglass dust as filler' thread..........

 

[blkvyyper]

Re: Question for the experts: What would you do?

Re: Question for the experts: What would you do?

jbcurt00,
Thanks for the reply, I was told not to start a new thread and to keep it all in this one, that's why it is like that. Haven't started a thread for resto of this boat but been taking pics as i go and will post them once i get the boat done. Money is funny around here so been taking longer than i expected not to mention how expensive it is to restore a boat. I'm still trying to think of whether to use epoxy or poly. want to use epoxy for the build since it is stronger but the cost...geez. Should have bought an aluminum boat...LOL

The garboard drain isn't threaded...it has a smooth bore in it, a flood waiting to happen as soon as something hangs on the plug and pulls it out...LOL gotta replace it.

BV

 

[GT1000000]

Re: Question for the experts on fiberglassing a 1976 ProCraft 1500 tri-hull

Re: Question for the experts on fiberglassing a 1976 ProCraft 1500 tri-hull

Howdy blkvyyper,

Finally tracked down your restore thread...just came aboard, so's I got me some reading to catch up on...

Here's the skinny on all of those holes...give or take...

Hope this helps...

L8r,
GT1M